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We solve some recurrences given by E. Munarini and N. Zagaglia Salvi proving explicit closed formulas for Whitney numbers of the distributive lattices of order ideals of the fence poset and crown poset. Moreover, we get explicit closed…

Combinatorics · Mathematics 2011-01-28 Alessandro Conflitti

We study the set of monomial ideals in a polynomial ring as an ordered set, with the ordering given by reverse inclusion. We give a short proof of the fact that every antichain of monomial ideals is finite. Then we investigate ordinal…

Logic · Mathematics 2007-05-23 Matthias Aschenbrenner , Wai-Yan Pong

In this paper we obtain bounds for integer solutions of quadratic polynomials in two variables that represent a natural number. Also we get some results on twin prime numbers. In addition, we use linear functionals to prove some results of…

General Mathematics · Mathematics 2021-02-25 B. M. Cerna Maguiña , Victor H. López Solís , Dik D. Lujerio Garcia

We study monomial cut ideals associated to a graph $G$, which are a monomial analogue of toric cut ideals as introduced by Sturmfels and Sullivant. Primary decompositions, projective dimensions, and Castelnuovo-Mumford regularities are…

Commutative Algebra · Mathematics 2021-12-09 Jürgen Herzog , Masoomeh Rahimbeigi , Tim Römer

In this paper we use some results related to regularity, Betti numbers and reduction of generic initial ideals, showing their stability in passing from an ideal to its initial ideal if the last has some simple properties.

Commutative Algebra · Mathematics 2013-10-16 Fabrizio Brienza , Anna Guerrieri

We show that for the edge ideals of a certain class of forests, the arithmetical rank equals the projective dimension.

Commutative Algebra · Mathematics 2007-05-23 Margherita Barile

The Wiener index is maximized over the set of trees with the given vertex weight and degree sequences. This model covers the traditional "unweighed" Wiener index, the terminal Wiener index, and the vertex distance index. It is shown that…

Combinatorics · Mathematics 2017-05-12 Mikhail Goubko

We present an explicit construction of a minimal cellular resolution for the edge ideals of forests, based on discrete Morse theory. In particular, the generators of the free modules are subsets of the generators of the modules in the…

Commutative Algebra · Mathematics 2019-02-08 Margherita Barile , Antonio Macchia

This paper demonstrates that extremal ideals can be used to great effect to compute integral closures of powers and symbolic powers of square-free monomial ideals. We show that the generators of these powers are images of the generators of…

Commutative Algebra · Mathematics 2026-02-06 Trung Chau , Art Duval , Sara Faridi , Thiago Holleben , Susan Morey , Liana Şega

Let X be a k-dimensional simplicial complex such that the (k-j-2)-dimensional homology of the links of all j-dimensional simplices in X vanishes. An upper bound is given on the (k-1)-th Betti number of X. Examples based on sum complexes…

Combinatorics · Mathematics 2017-03-17 Amir Abu-Fraiha , Roy Meshulam

In the present paper, we consider upper bounds of higher linear syzygies i.e. graded Betti numbers in the first linear strand of the minimal free resolutions of projective varieties in arbitrary characteristic. For this purpose, we first…

Algebraic Geometry · Mathematics 2014-11-21 Kangjin Han , Sijong Kwak

In this article, we study the linearity of the minimal free resolution of powers of facets ideals of simplicial trees. We give a complete characterization of simplicial trees for which (some) power of its facet ideal has a linear…

Commutative Algebra · Mathematics 2026-01-14 Ajay Kumar , Arvind Kumar

In their paper on multiplicity bounds (1998), Herzog and Srinivasan study the relationship between the graded Betti numbers of a homogeneous ideal I in a polynomial ring R and the degree of I. For certain classes of ideals, they prove a…

Commutative Algebra · Mathematics 2007-05-23 Leah Gold , Hal Schenck , Hema Srinivasan

Let $G$ be a finite simple graph on $n$ non-isolated vertices, and let $J_G$ be its binomial edge ideal. We determine almost all pairs $(\text{projdim}(J_G),\text{reg}(J_G))$, where $G$ ranges over all finite simple graphs on $n$…

Commutative Algebra · Mathematics 2025-01-15 Antonino Ficarra , Emanuele Sgroi

We derive a lower bound for all Levine-Tristram signatures of positive braid links, linear in terms of the first Betti number. As a consequence, we obtain upper and lower bounds on the ratio of fixed pairs of Levine-Tristram signature…

Geometric Topology · Mathematics 2021-09-13 Sebastian Baader

In this paper, we study a class $\mathcal{C}$ of squarefree monomial ideals $I\subseteq R=\mathbb{K}[x_1,\dots,x_n]$ over a field $\mathbb{K}$, defined by the condition that $\dim R/I$ equals the maximum degree of the minimal generators of…

Commutative Algebra · Mathematics 2026-03-19 Mohammed Rafiq Namiq

We determine upper and lower bounds for the number of maximum matchings (i.e., matchings of maximum cardinality) $m(T)$ of a tree $T$ of given order. While the trees that attain the lower bound are easily characterised, the trees with…

Combinatorics · Mathematics 2013-04-09 Clemens Heuberger , Stephan Wagner

We show that the expected size of the maximum agreement subtree of two $n$-leaf trees, uniformly random among all trees with the shape, is $\Theta(\sqrt{n})$. To derive the lower bound, we prove a global structural result on a decomposition…

Combinatorics · Mathematics 2018-09-13 Pratik Misra , Seth Sullivant

We define the uniform face ideal of a simplicial complex with respect to an ordered proper vertex colouring of the complex. This ideal is a monomial ideal which is generally not squarefree. We show that such a monomial ideal has a linear…

Combinatorics · Mathematics 2013-08-07 David Cook

We show that the signature of a positive braid link is bounded from below by one-quarter of its first Betti number. This equates to one-half of the optimal bound conjectured by Feller, who previously provided a bound of one-eighth.

Geometric Topology · Mathematics 2025-12-15 Joshua Evan Greene , Livio Liechti